Improvement in locking-latches



H. A. CHASE.

LOCKING LATCH.

No. 189,191. Patented April-3,1877.'

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NPEERS. PHDTO-LITHOGRIPHER, WASHXNGTON. D. C.

UNITED STATES PATENT OFFICE.

HENRY A. CHASE, OF HARTFORD, CONNECTICUT, ASSIGNOR OF ONE-HALF HIS RIGHT TO S. A. HUBBARD AND C. H. CLARK, OF SAME PLACE.

IMPROVEMENT IN LOCKING-LATCHES.

Specification forming part of Letters Patent No. 189,i91, dated April 3, 1877; applicationled March 2, 1877.

To all whom it may concern Be it known that I, HENRY A. CHASE, of Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Door- Locks and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawings, making a part of this specification.

My invention relates to certain novel improvements in that class of locks having the key-holes on opposite sides placed out of line, to prevent tampering through the key-hole opposite to that side of the case from which the bolt has been locked.

My invention consists in forming the spring latch-bolt, which, in its normal condition, is extended beyond the front of the case, with shoulders, and locating an independent locking-bar and spring-tumbler above and below the latch-bolt, each accessible through different key-holes, only in opposite sides of the casing, as will be hereinafter more fully set forth.

To enable those skilled I will describe the construction .and operation of my improved lock, referring'by letters to the accompanying drawing, in which- Figure 1 is a plan view, with one side of the casing removed, of a lock embracing the features of my invention, with the latch-bolt free to be forced in and out, as an ordinary spring latch. Fig. 2 is a similar view with the inde pendent locking-bars shot forward to prevent the retraction of the latch-bolt, and with the knob-spindle and cam removed. Fig. 3 is a t similar view with the upper tumbler removed,

and the upperbar only shot into position by means of a key from the opposite side of the casing; and Fig. 4,.a section at the line a; w,

' Fig. 3.

the passage of the knob-spindle o, and an arched rib, d, to lreceive the hub of the cam E, the extended portions of which come in contact with the ends of the rib, and force the bolt back when the knob-spindle c is rotated in either direction. The tail of the latch-bolt is rounded and adapted to lie within a spiral spring, F, employed to keep the bolt projected. G Gr and g are posts parallel with the latch-bolt, and sufficiently distant therefrom to permit the introduction and longitudinal movement of the independent locking-bars H, which are provided with projections 1 1, to receive the key, and by which the bars are shot 'forward and retracted. These bars are also provided near their forward ends with upright projections e', which lie in notches f of the tumblers when the latch-bolt isv free, as shown at Fig. 1, or in front of the forward ends of the tumblers when the latch-bolt is locked against retraction, as shown at Figs. 2 and 3. lI I-are vibrating tumblers, one on either side of the latch-bolt, pivoted at J J, and kept distended by a U-shaped spring, K, the forward pair of posts G G sustaining the forward ends of the tumblers and preventing sred to lock the bolt against retraction, the

key is inserted, as shown in section at Fig. 3, and, being turned, comes in contact with the tumbler I, swinging its forward notched end inwardly and oii' from the upright projection e of the locking-'bar H, thus releasing the latter. The key, entering between the points 1 1 of the bar H, shoots it forward against the shoulder a, behind the head of the latch-bolt, the U -shaped spring forcing` the tumbler back, the end ofthe same falling behind the upright projection e, and holding the latch-bolt and bar H against retraction until the key shall have been inserted, the tumbler lifted, and the bar H drawn back by the reverse movement of the key.

It will be readily seen that when the lower bar H has been projected forward to lock the spring-tumblers I, arranged to operate substantially as hereinbefore set forth.

Witness my hand. and seal this 8th day of February, A. D. 1877.

HENRY A. CHASE. [L s] Witnesses:

LYMAN A. WILEY, FRANK L. HAMILTON. 

